The father of the 16-month-old child shot dead in his stroller is not cooperating with investigators trying to find his son’s killer, according to cops.Little Antiq Hennis was shot in the head in Brownsville Sunday night.The boy’s 23-year-old father, Anthony Hennis, has been arrested 23 times, police sources said, mostly for drugs.Detectives believe the shooter was attempting to get back at Hennis for an earlier dispute, according to sources.“He was definitely the intended target," a police source said.Hennis is refusing to help investigators, NYPD Commissioner Raymond Kelly said Monday.But Anthony’s grandmother, Lenore Steel, 72, who was sitting nearby when the baby was shot, said her grandson would do anything for his baby.“He can't live without that baby,” Steel said. “He's always with him. That baby is his life."